[0001] THIS INVENTION relates to the handling of radioactive materials. More particularly,
the invention relates to a radioactive material handling assembly and to a method
of operating such a radioactive material handling assembly.
[0002] Shielded installations are typically used in applications for safe handling, e.g.
examination and/or treatment, of radioactive materials. Such installations are typically
constructed of a shielding material which is opaque to radioactivity, and define a
holding or handling chamber, in which a radioactive material can be contained and
examined and/or treated. A disadvantage of such installations is that once one type
of radioactive material has been introduced into the handling chamber, the chamber,
and accordingly the installation, must be de-contaminated before it can be used for
a different radioactive material, thereby to prevent cross-contamination between the
different radioactive materials. Apart from thus generating large volumes of radioactive
waste, a further, related disadvantage is that such installation decontamination operations
are typically very time-consuming, resulting in unacceptably excessive time requirements
for conducting successive operations involving a variety of radioactive materials,
such as routine tests, experiments, or small scale radiochemical production operations.
Alternatively, a plurality of such installations is required, inevitably leading to
multiplication of facilities and infrastructure. Conducting multiple operations in
a short time, therefore, will typically be beyond the capability of most facilities.
The Applicant believes that the present invention will find application particularly
in alleviating the abovementioned disadvantages.
[0003] GB 947 074 discloses a radioactive material handling assembly, suitable for the metallograhic
study of radioactive samples involving several unit operations being performed on
each sample, which includes an outer housing, a series of sealed inner cells, which
defines a series of radioactive material containment / handling chambers, sealably
connected together via a remotely controlled conveyor carrying a series of buckets
that are sealably connectable to any one of the cells, the cells being individually
removably mountable inside the outer housing, such that each cell can be transported
to a decontamination region inside the outer housing, the inner cells being substantially
complementary in shape to the outer housing when both are seen in horizontal section
such that, when the inner cell is mounted inside the outer housing, at least some
of the walls of the inner cells are adjacent the corresponding walls of the outer
housing, and handling means operable from outside the inner cell to handle radioactive
materials located in the containment / handling chamber, with at least one of the
outer housing and the inner cell being predominantly of a shielding material which
is opaque to radioactivity.
[0004] Thus, according to a first aspect of the invention, there is provided a radioactive
material handling assembly, which includes
an outer housing;
an inner cell which defines a radioactive material containment / handling chamber
and which is individually removably mountable inside the outer housing, the inner
cell being complementary in shape to the outer housing when both are seen in horizontal
section such that, when the inner cell is mounted inside the outer housing, each wall
of the inner cell is adjacent a corresponding wall of the outer housing, the inner
cell being interchangeable with a plurality of other inner cells which are individually
removably mountable inside the outer housing; and
handling means operable from outside the inner cell to handle radioactive materials
located in the containment / handling chamber,with at least one of the outer housing
and the inner cell being predominantly of a shielding material which is opaque to
radioactivity,
characterized in that
two of the handling means are provided, the handling means being mounted to respective
walls of the inner cell, which walls are angularly spaced relative to each other about
a vertical line of intersection between the walls or projections thereof such that
the handling means are thus also angularly spaced from each other, when the cell is
seen in plan view.
[0005] Unless otherwise indicated, by "handle" or "handling" is meant handling and/or treatment
of radioactive materials located inside the inner cell, and by "handling means" is
correspondingly meant means for carrying out such handling. Similarly, "containment
/ handling chamber" refers to the chamber defined by the inner cell in which containment
of radioactive materials and such handling of radioactive material is carried out,
when the inner cell is mounted inside the outer housing.
[0006] By "predominantly" is meant that all the major components, such as the walls, etc
of said at least one of the outer housing and the inner cell are of the shielding
material which is opaque to radioactivity. Preferably, the outer housing is predominantly
of shielding material which is opaque to radioactivity. Thus, the major components
of the outer housing, such as its walls, etc may be of lead.
[0007] The assembly may include a plurality of inner cells which are individually removably
mountable inside the outer housing. Typically, the assembly includes an inner cell
for each radioactive material which is to be handled in the assembly.
[0008] The outer housing and the inner cell thus have complementary shapes, typically when
viewed in horizontal section, such that the inner cell can be snugly received and
mounted within the outer housing.
[0009] The handling means comprise manipulating means inside the containment / handling
chamber, which is hereinafter also referred to simply as "the handling chamber". The
manipulating means is thus arranged to carry out manipulation operations inside the
handling chamber. The manipulation means may comprise a pair of tongs or the like.
The handling means may include attachment means connecting the manipulating means
to a wall of the inner cell. The attachment means may thus be configured to enable
movement of the manipulating means while connected to walls of the inner cell. Still
more particularly, the attachment means may be flexible attachment means, such as
flexible boots, which are sealably mounted to walls of the inner cell such that containment
integrity of the inner cell is maintained. Movement of the handling means within the
handling chamber is then restricted by the extent to which the flexible attachment
means are capable of flexing or deforming.
[0010] Each handling means may be removably connected to its associated attachment means,
thereby enabling the use of a variety of handling means in association with one attachment
means.
[0011] The inner cell, and accordingly the handling chamber, may be provided with storage
space for storing additional handling means which are removably connectable to the
attachment means.
[0012] The assembly may include control means for the handling means. The control means,
in use, is operable to control operation of the handling means from a position remote
from the handling chamber, preferably from a position remote from the inner cell,
when the inner cell is mounted in the outer housing. The handling means and associated
control means are provided separately respectively in the inner cell and on the outer
housing, the control means being operatively connectable to its associated handling
means when the inner cell is mounted in the outer housing. Preferably, complementary
pairs of handling means and control means are provided in corresponding positions
in operationally adjacent walls of the inner cell and outer housing, i.e. walls which
are adjacent when the inner cell is mounted in the outer housing.
[0013] Each control means may comprise a control rod, one end portion of the control rod
being connected or connectable to the handling means and the other end portion of
the control rod extending beyond the confines of the outer housing and being provided
with a user control interface, such as a pistol grip. The control rod may be pivotally
mounted in a wall of the outer housing by means of a pivotal mounting, thereby to
direct pivotal movement of the handling means when connected thereto. It will be appreciated
that the mountings which connect the control means to the outer housing may also be
of radiation opaque material. Typically, the mountings may be lead ball-sockets having
a radiation shielding power of at least 100mm lead. Control rods of various lengths
may be employed with each handling means, thereby to provide a variety of operating
ranges of the handling means in the handling chamber. It will be appreciated that
the length of a control rod thus also restricts the extent to which an associated
handling means thereof is displaceable inside the handling chamber, the operating
range of the handling means thus being determined by the deformability of its associated
connecting member and the length of its associated control rod.
[0014] The assembly thus includes the two handling means which are provided at angularly
spaced positions about a vertical line of intersection between tangents to a connection
point of each handling means to a wall of the inner cell, said angular spacing typically
being 90°. The assembly thus includes two handling means which are each provided in
a different wall of the inner cell, the walls being angularly spaced from each other
about a vertical line of intersection between the walls, e.g. at a right angle to
each other, if the walls are adjacent each other, or about a vertical line of intersection
between projections of the walls if the walls are not adjacent each other. It will
be appreciated that connection points of the handling means in the walls are then,
effectively, also spaced at a right angle from each other about said line of intersection
which is effectively also a line of intersection between tangents to the connection
points of the handling means in the walls.
[0015] It is to be appreciated that, in the embodiment as hereinbefore described, the control
means associated with each of the angularly spaced handling means are also angularly
spaced from each other in the same fashion as their associated handling means and
are thus located at angularly spaced positions in walls of the outer housing corresponding
to positions of the angularly spaced handling means.
[0016] The assembly may include viewing means in the outer housing and the inner cell, for
visual inspection of radioactive materials contained in and being handled inside the
handling chamber when the inner cell is mounted inside the outer housing. The viewing
means may be in the form of at least one window in a wall of each of the inner cell
and the outer housing, the windows providing a line of sight from a position external
to the assembly, to the handling chamber when the inner cell is mounted inside the
outer housing.
[0017] At least one of the windows may be of radiation opaque material. The radiation shielding
window may have a radiation shielding power equivalent to at least 75mm lead. Preferably,
the radiation shielding window has a radiation shielding power equivalent to about
100mm lead. The inner cell window may then typically be of polycarbonate.
[0018] When the assembly includes angularly spaced handling means and associated angularly
spaced control means as hereinbefore described, a window or other viewing means may
be provided in a wall of the outer housing, between the angularly spaced control means,
which window then provides a line of sight into the handling chamber through the inner
cell window when the inner cell is mounted inside the outer housing. If the angularly
spaced handling means are provided in angularly spaced walls as hereinbefore described,
the walls may be connected by a connecting wall in which the window is provided. The
connecting wall may be obliquely oriented relative to said angularly spaced walls.
It will be appreciated that, in such an embodiment, the angularly spaced walls are
then not adjacent each other and are accordingly angularly spaced about a vertical
line of intersection between projections thereof.
[0019] It is envisaged that, when the assembly includes such angularly spaced handling means,
and associated angularly spaced control means, and a window is provided in a wall
of the outer housing between the angularly spaced control means, an operator of the
assembly will, in use, operate the angularly spaced handling means by means of the
angularly spaced control means from a position between the control means adjacent
the window provided in the oblique wall, between the angularly spaced control means.
[0020] The handling means, or at least two other handling means, and their associated control
means, may be positioned at different levels in the inner cell and outer housing.
Thus, the handling means and associated control means are vertically spaced from each
other. In a preferred embodiment of the invention, the angularly spaced handling means
and their associated angularly spaced control means are vertically spaced from each
other.
[0021] The inner cell may be provided with handling chamber access means for introducing
materials, particularly non-radiating materials, into, and withdrawing such materials
out of, the handling chamber.
[0022] Typically, the handling chamber access means comprises a double door assembly, i.e.
an inner and an outer door assembly, such that the integrity of the handling chamber
is not compromised during the introduction of materials into, or withdrawal of materials
out of, the handling chamber. More particularly the inner cell may be provided with
at least one
Double Porte de Transfert Etanche™ ("DPTE") port. Typically, the inner cell is provided with two DPTE ports of different
sizes. In a preferred embodiment of the invention, the inner cell is provided with
at least one 105-DPTE port and at least one 270-DPTE port.
[0023] Inner doors of the DPTE ports may be operated or actuated by the handling means.
Typically, a DPTE port may be located within the operating range of at least one handling
means in the inner cell such that an inner door of the DPTE port can be operated by
the handling means in which operating range it is located. In a preferred embodiment
of the invention, at least one DPTE port is provided in direct, i.e. perpendicular,
alignment with at least one handling means. Thus, at least one DPTE port may be provided
in a wall of the inner cell opposite to the wall of the inner cell in which the handling
means associated therewith is provided.
[0024] In use, when the inner cell is provided with a DPTE port and a door of the DPTE port
is to be opened, radioactive materials will preferably be positioned in the handling
chamber such that passage of a radiation beam through the door is avoided. In other
words, in use, before a DPTE door is opened, radioactive materials are typically positioned
inside the handling chamber such that they are not in direct alignment with a DPTE
port.
[0025] The inner cell may also be provided with a bottom loading port for loading materials,
particularly radioactive materials, into and out of the handling chamber through the
bottom of the cell, and closing means which closes and seals the bottom loading port
from the inside of the handling chamber. The loading port may be configured to receive
or dock containers, or pots as they are known in the art of the invention, containing
radioactive material which is to be loaded into the handling chamber. The closing
means may be in the form of a lid. The lid is thus operable only from within the handling
chamber. The lid may thus be operated by the handling means.
[0026] The outer housing may be provided with bottom loading port access means. The bottom
loading port access means may be associated with and provide access to the bottom
loading port of the inner cell from outside the assembly, when the inner cell is mounted
in the outer housing. The bottom loading port access means may comprise an opening
in the bottom of the outer housing at an operationally corresponding location to the
bottom loading port of the inner cell and may be provided with a removable cover in
the form of a shielding slot or stopper, which will hereinafter be referred to as
a "key", which is openable or removable from outside the outer housing. The key may
be connectable to the lid of the bottom loading port when the inner cell is mounted
inside the outer housing and may thus lock the lid of the bottom loading port in a
closed position and prevent opening thereof when connected thereto, thereby preventing
inadvertent opening of the bottom loading port lid from the inside of the inner cell
when no container or pot is received in or docked against the bottom loading port.
Typically, the key may engage or slot into the bottom loading port lid by means of
a bayonet fitting. The key may be of a radiation opaque or shielding material, e.g.
which has a radiation shielding power equivalent to 50mm lead. Thus, the key provides
the required radiation shielding for the bottom loading port in the normal closed
state.
[0027] To provide further radiation shielding, a section of radiation shielding material,
e.g. a lead ring, may be incorporated into the trolley. The ring may provide further
radiation shielding of the bottom loading port when the key is disconnected from the
lid.
[0028] To facilitate safe transport of containers with radioactive source or sample materials
into and from the inner cell of the radioactive material handling assembly, a container
loading assembly including container displacement means for docking containers against
the bottom loading port through the bottom loading port access means may be provided
on the outer housing. The container displacement means may be operable to displace
a container or pot mounted thereon from outside the radioactive material handling
assembly, through the bottom loading port access means of the outer housing towards
the bottom loading port of the inner cell. Typically, the container displacement means
is configured to support a container mounted thereon and also to displace the container
mounted thereon into axial alignment with the loading port access means. The container
displacement means may further be configured to displace the container in axial alignment
with the loading port access means, i.e. vertically. It will be appreciated that,
as mentioned hereinbefore, the container may also be referred to as a "pot", as is
common in the field of the invention.
[0029] The container displacement means may include a trolley, which is supported by a rail
track which is suspended from the outer housing. The trolley is typically configured
to receive thereon, in addition to the container, the key of the bottom loading port
access means when the key is removed from the bottom loading port access means. In
one embodiment, the trolley may be provided with a key receptacle thereon, which key
receptacle receives the key when it has been removed from the bottom loading port
access means. Thus, in use, when the key is being removed, the key receptacle is positioned
in axial alignment with the bottom loading port and loading port access means, thereby
to receive the key once it is removed. The trolley may also be configured such that
the container can only be moved into a position in axial alignment with the loading
port when the key has been removed from the bottom loading port access means and has
been stowed in the receptacle. Typically, when the key is in a closed or locked position,
the spatial relationship between the trolley and key is such that the key prevents
horizontal movement of the trolley, thus locking it in position, e.g. by partially
extending into the recess defined by the key receptacle.
[0030] The loading assembly means may include hoisting means for hoisting a container towards
the bottom loading port in a closed condition. The loading assembly may therefore
be provided with hoisting means. The hoisting means may be in the form of a mechanical
lever or pulley system, or an axial drive means such as a hydraulic piston. The loading
assembly may further be configured to open the lid of the container when, and only
when, it is positioned at a predetermined height in close proximity to, but not yet
docked against the bottom loading port, such that radiation exposure is prevented
and handling chamber integrity is maintained throughout the hoisting and docking operation.
[0031] Opening the container may be effected by means of a horizontal sliding plate, which
is mounted on the loading assembly transversely to a hoisting direction and at the
abovementioned predetermined height. The sliding plate typically has an opening and
circumferential clamping means of larger diameter than the lid of the container. Thus,
in use, the lid is clamped to the sliding plate, the container is slightly lowered
and the lid is removed from above the container so that the open container can then
be raised to its docking position against the bottom loading port. Typically, the
bottom loading port lid is then opened from the inside of the cell to provide access
to the radiation source or sample material inside the container.
[0032] The loading assembly may be configured to dock containers of different diameter to
the bottom loading port. In one embodiment, this is effected by having mounted to
the hoisting means, for each container of a particular diameter, a matching outer
spacer ring or sleeve, preferably of radiation opaque material, for receiving the
container, with the outer spacer, ring or sleeve having a fixed outer diameter and
shaped to match a carriage of the hoisting means as well as the bottom loading port
opening. The ring or sleeve thus fits snugly around the container such that, when
the lid of the container has been removed, the container and spacer ring docks radiation
leak free to the bottom loader port of the inner cell.
[0033] The inner cell may also be provided with at least one ventilation inlet to the handling
chamber and at least one exhaust outlet from the handling chamber. The ventilation
inlet and the exhaust outlet may be provided, respectively, with inlet and outlet
filters. In a preferred embodiment of the invention, the inlet and outlet are each
provided with a filter arrangement comprising two filter elements, one element positioned
inside the inner cell and another element provided outside the inner cell, in the
space between the inner cell and the outer housing. It is envisaged that, by such
an arrangement, replacement and service of the filters as well as interchanging the
inner cells can be effected without compromising the integrity of the handling chamber.
Preferably, the filter arrangements are positioned such that each inner filter element
is in line with, or within operating range of, at least one handling means so that
service and replacement of the inner filter element in each filter arrangement can
be effected from inside the handling chamber by means of the handling means, without
compromising handling chamber integrity.
[0034] The inlet filter arrangement on the inner cell may have a corresponding service access
means in the form of an opening in the outer housing, which opening may be shielded
by a radiation opaque plug or stopper, thereby to prevent radiation emission through
the inlet and its associated filter arrangement. The stopper may be removable, thereby
to allow replacement of the outer inlet filter element through said access means.
[0035] The exhaust outlet and outlet filter arrangement may also have a service access means
for replacing the outer exhaust filter element, which may be shielded by a lead plug
or stopper, generally in similar fashion to the plug or stopper on the inlet, thereby
to prevent radiation emission through the outlet. The outer filter element of the
exhaust outlet filter arrangement may be connected by means of an exhaust line to
a ventilation system of a laboratory or other site for accommodating the radioactive
material handling assembly. The exhaust line may typically pass through the service
access means plug such that radiation is prevented from leaking through the plug from
the handling chamber through the exhaust outlet. In a preferred embodiment this may
be achieved by guiding the exhaust line through the plug along a specially designed
void, typically in the form of a maze or labyrinth channel, such that it will allow
easy passage of the exhaust line, but prevent radiation leakage through the plug.
[0036] In use, a low pressure is created inside the handling chamber due to the outflow
of air through the exhaust outlet into the ventilation system. Air is thus drawn into
the inner cell through the ventilation from the surrounding air outside the inner
cell within the outer housing and thus, as a consequence, also from outside the outer
housing, thereby creating a net inflow of uncontaminated air from outside the outer
housing into the inner cell.
[0037] As hereinbefore described, the outer housing may have walls of radiation opaque or
shielding material, such as lead. Preferably, the outer housing comprises lead wall,
floor and roof panels, comprising interlocking lead bricks or solid lead slabs, which
are supported by a high integrity support frame.
[0038] The inner cell may have walls of stainless steel.
[0039] The radiation shielding power of the outer housing may, for walls thereof, be equivalent
to at least 50mm lead.
[0040] At intersections between adjacent walls of the housing, where a danger of radiation
emission exists, in that a radiation beam may pass through openings and/or sections
of low radiation shielding of the intersection, commonly referred to in the art of
the invention as a "beam path", additional radiation shielding may be provided.
[0041] The outer housing may also be provided with a carriage on which the inner cell may
be transported into or out of the housing. Inside the outer housing, the cell may
be stabilized on the carriage by securing the cell to stabilization mountings inside
the outer housing.
[0042] The outer housing may also be provided with access means to an interior thereof.
More particularly, the outer housing may be provided with at least one primary or
main door through which the inner cell is inserted into the outer housing. In a preferred
embodiment of the invention, the door of the outer housing is a slidably, vertically
displaceable trapdoor, operation of which may be controlled by a counterweight arrangement.
[0043] The outer housing may also be provided with secondary doors which provide access
to the DPTE ports in the inner cell when the cell is mounted inside the outer housing.
The secondary doors are thus preferably arranged in positions in the outer housing
which correspond to the positions of DPTE ports in the inner cell when the inner cell
is mounted in the outer housing. In a preferred embodiment of the invention, at least
one DPTE port, typically a 270-DPTE port, is provided in a wall of the inner cell
which is operationally adjacent the main door of the outer housing, the main door
thus providing access to such a DPTE port.
[0044] The radiation shielding power of doors of the outer housing may be equivalent to
at least 50mm lead.
[0045] The inner cell may be provided with connection means for linking additional services,
in addition to the handling means, such as electricity, gas, vacuum, water and compressed
air to the handling chamber. Such connection means are preferably configured such
that linkage of additional services to the handling chamber does not compromise the
integrity thereof at any time during connection or disconnection. The connection means
for connection of the abovementioned services are preferably provided in one wall,
which is preferably a wall in which a DPTE port is provided. In an embodiment wherein
the connection means are thus provided, the DPTE port is preferably a 270-DPTE port
and the wall is preferably a wall of the inner cell which is operationally adjacent
a main door of the outer housing.
[0046] The outer housing may be provided with a chamber for housing radiation detection
and/or radiation monitoring equipment. The chamber may be of radiation shielding material
having a radiation shielding power equivalent to 50mm lead. The inner cell may also
be provided with radiation detection and/or monitoring equipment.
[0047] The outer housing may be provided with inner cell lighting means, the lighting means
providing light to the inner cell through the inner cell window. The lighting means
may be in the form of electrical lights which are provided in light sockets each of
which is mounted on a base of radiation shielding material having a radiation shielding
power equivalent to 50mm lead, in the form of a plug or slot which fits from the outside
through the roof of the outer housing in a radiation leakage free manner.
[0048] The assembly may have warning means, such as one or more alarms. At least one alarm
may operate in conjunction with the radiation detection and/or monitoring equipment
and may be configured to indicate an unacceptable level of radiation emission from
the assembly. Another alarm may operate in conjunction with the ventilation system
to indicate a failure or insufficient flow of ventilation air.
[0049] According to a second aspect of the invention, there is provided a method of operating
a radioactive material handling assembly according to the first aspect of the invention,
to handle radioactive materials therein, the method including
inserting, individually, an initial or first inner cell into the outer housing of
the assembly such that the initial or first inner cell is individually mounted inside
the outer housing with each wall thereof being adjacent a corresponding wall of the
outer housing;
handling an initial or first radioactive material inside the containment / handling
chamber of the initial or first inner cell from a position outside the outer housing;
removing the initial or first inner cell from the outer housing; and
inserting a second inner cell into the outer housing after removal of the initial
or first inner cell from the outer housing and handling a second radioactive material
inside the containment / handling chamber of the second inner cell, the second radioactive
material being different to the initial or first radioactive material,
characterized in that
the handling of the radioactive materials inside the containment / handling chambers
of the inner cells is effected by means of two handling means mounted to respective
walls of the inner cells, which walls are angularly spaced relative to each other
about a vertical line of intersection between the walls or projections thereof such
that the handling means are thus also angularly spaced from each other, when the cells
are seen in plan view.
[0050] The second radioactive material is thus different to the initial or first radioactive
material, e.g. having different radiation emission properties to that of the first
radioactive material.
[0051] The method may still further include servicing third and further radioactive materials,
different to the first and second radioactive materials, respectively in third and
further inner cells which are in turn loaded or inserted into the outer housing.
[0052] In a preferred embodiment of the invention, the method may include handling similar
radioactive materials in the assembly in the same inner cell of the assembly and handling
different radioactive materials in the assembly each in a separate inner cell of the
assembly.
[0053] The method may include loading a radioactive material into its associated inner cell
after the inner cell has been inserted into the outer housing. Alternatively, the
method may include loading the radioactive material into its associated inner cell
before the inner cell has been inserted into the outer housing.
[0054] The method may also include removing a radioactive material from its associated inner
cell before the inner cell is removed from the outer housing. Alternatively, the method
may include removing the radioactive material from its associated inner cell after
the inner cell has been removed from the outer housing.
[0055] The loading into and/or removing out of the inner cell of radioactive material after
the inner cell has been removed from the outer housing is particularly advantageous
when such materials are "soft" radiators, i.e. emitting only low intensity radiation,
which is sufficiently contained by the shielding power of the inner cell itself.
[0056] The method may further include decontaminating the outer housing after an inner cell
has been removed therefrom and before another inner cell is inserted therein.
[0057] The method may also include decontaminating the inner cell, after removal of the
inner cell from the outer housing.
[0058] The method may further include sealing the inner cell before or after removal thereof
from the outer housing thereby to maintain its integrity.
[0059] The invention will now be described in more detail, with reference to the following
diagrammatic drawings.
[0060] In the drawings:
FIGURE 1 shows a front view of an assembled radioactive material handling assembly
in accordance with the invention;
FIGURE 2 shows one side view of the handling assembly of Figure 1;
FIGURE 3 shows a rear view of the handling assembly of Figures 1 and 2;
FIGURE 4 shows another side view of the handling assembly of Figures 1 to 3;
FIGURE 5 shows a horizontal section of the handling assembly of Figures 1 to 4;
FIGURE 6 shows a disassembled perspective view of the handling assembly of Figures
1 to 5; and
FIGURE 7 shows a partial cutaway side view of a container loading assembly of the
handling assembly of Figures 1 to 6 and indicates portions of radiation shielding
material in shading.
[0061] In the drawings, reference numeral 10 generally indicates a radioactive material
handling assembly in accordance with the invention.
[0062] The assembly includes an outer housing 12 and an inner cell 14 (which is shown in
some detail in Figures 4, 5 and 6), the inner cell 14 being removably mounted inside
the outer housing 12 on tracks (not shown), which facilitate insertion of the inner
cell 14 into the outer housing 12. The inner cell 14 is stabilized on the tracks inside
the outer housing 12 by connection to anchoring or stabilization mountings (not shown)
provided inside the outer housing 12.
[0063] The inner cell 14 is of stainless steel and defines a containment / handling chamber
16 (hereinafter also simply referred to as "the handling chamber 16") which, in use,
contains a radioactive material which is to be handled or serviced in the assembly
10. The inner cell 14 is provided with a polycarbonate window 22, which constitutes
an upper, diagonally oriented wall of the inner cell 14.
[0064] As illustrated most clearly in Figure 5, the inner cell and outer housing have complementary
shapes in horizontal section. More particularly, the inner cell 14 and outer housing
12 have, respectively, two sidewalls, respectively 18a, 18c and 20a, 20c, two endwalls,
respectively 18b, 18d and 20b, 20d and one oblique wall, respectively 18e and 20e.
When the inner cell 14 is mounted in the outer housing the sidewalls 18a, 20a and
18c, 20c, the end walls 18b, 20b and 18d, 20d, and the oblique walls 18e, 20e are
thus in positions adjacent each other.
[0065] The sidewalls 20a and 20c, the endwalls 20b and 20d and the oblique wall 20e of the
outer chamber 12 are of lead, typically being made up of interlocking lead bricks
or solid lead slabs which are supported by a high integrity support frame. The outer
chamber 12 also has a lead floor and a lead roof.
[0066] A window 24 is provided in the oblique sidewall 20e of the outer housing 12, the
window having a radiation shielding power equivalent to 100mm lead and providing a
line of sight into the handling chamber 16 through the inner cell window 22.
[0067] Handling means in the form of tongs 26 are connected to the walls 18b, 18c of the
inner cell 14 by means of flexible boots 30. Complementary control means 28, each
comprising a control rod 28.1 and a pistol grip user interface 28.2, are connected
to walls 20b, 20c of the outer housing 12 by lead ball-sockets 32 which render the
control means 28 pivotally and axially (slidably) displaceable in the walls 20b, 20c.
The tongs 26 of the wall 18b are at a different level to the tongs 26 of the wall
18c.
[0068] The rods 28.1 of the control means 28 are operatively removably connected to their
associated tongs 26 such that a clamping action of the tongs 26 is controlled by operation
of the pistol grips 28.2 and such that displacement of the tongs 26 is directed by
pivotal and sliding displacement of the rods 28.1 in the sockets 32.
[0069] The tongs 26 and their associated control means 28 are positioned respectively in
walls 18b, 18c of the inner cell and adjacent walls 20b, 20c of the outer housing,
which walls 18b, 18c and 20b, 20c are rectangularly oriented relative to each other
about vertical lines of intersection "I1" and "I2" between projections "P" of the
walls 18b, 18c and 20b, 20c. The tongs 26 and their associated flexible boots 30 and
control means 28 are thus effectively rectangularly, or generally transversely, oriented
from each other.
[0070] The inner cell 14 is provided with two DPTE ports, comprising a 270-DPTE port 34.1
and a 105-DPTE port 34.2, respectively provided in sidewalls 18d and 18a of the inner
cell 14. The DPTE ports 34.1, 34.2 are respectively aligned with the handling means
26 in the sidewalls 18b and 18c of the inner cell 14.
[0071] The end wall 20d of the outer housing 12 is in the form of a sliding door arrangement
comprising an upper door panel 36a and a lower door panel 36b which are slidably mounted
parallel in tracks 38 which form part of a high integrity support frame 39 on which
the outer housing 12 is supported. The door panels 36a, 36b are controlled by a pair
of connecting cables running on pulleys (not illustrated) such that each panel 36a
and 36b forms a counterweight for the other and such that the panels 36a, 36b can
be easily slidingly displaced towards or away from each other, thereby selectively
to allow access to an interior of the outer housing 12.
[0072] The inner cell 14 includes a bottom loader port 40 which is closed off by a lid 42,
the lid 42 being openable only from inside the handling chamber 16. The port 40 is
configured to receive or dock therein a radioactive material container, typically
in the form of a pot 45, for loading radioactive and other materials into and out
of the chamber 16.
[0073] The outer housing 12 is provided with bottom loader port access means 41 (Figure
7) through which access to the port 40 of the inner cell 14 is enabled from outside
the outer housing 12 when the inner cell 14 is mounted inside the outer housing 12.
The port access means 41 is in the form of an opening in the lead floor of the outer
housing 12, this opening being closed off by a removable lead shielding cover or slot,
hereinafter referred to as a key 43, which, when covering the opening, is connected
to the lid 42 of the bottom loader port 40 by means of a bayonet fitting 43.1, thereby
to lock the lid 42 in place when connected thereto and to prevent opening of the lid
42. Thus, the key 43 locks the lid 42 in the normal closed state of the port 40. The
key 43 is operable by a handle 46.5. A portion 43.2 of the key 43 is lead and thus
provides radiation shielding to the bottom loader port 40 and the bottom loader port
access means 41 when engaged with the lid 42.
[0074] The outer housing 12 is further provided with a container loading assembly 46, the
assembly 46 including a trolley 46.2, which is supported on a horizontal rail track
46.3 which is connected to the outer housing 12. The trolley 46.2 is provided with
container displacement means 46.1, mounted on one end of the trolley 46.2, and with
a bottom loading port key receptacle 46.4 on the other end of the trolley 46.2. The
end of the trolley 46.2 to which the key receptacle 46.4 is mounted is provided with
a lead ring 46.6 (only a section being visible) which provides further radiation shielding
when the key 43 is disengaged from the lid 42. The displacement means 46.1 includes
a hoist mechanism 44 comprising a carriage 44.4 which is connected to sleeves 44.3
which are slidably mounted on vertical pillars 44.1 on the displacement means 46.1.
In use, the pot 45 is supported on the carriage 44.4, which is vertically displaceable
in axial alignment with the port 40 of the inner cell 14 through the port access means
41, by means of a pair of connecting cables (not shown) running on pulleys 44.2.
[0075] In a normal closed or locked position (not shown), the key 43 engages a bayonet fitting
(not shown) provided on the lid 42 by means of a complementary bayonet fitting 43.1.
In the closed or locked position, the key 43 extends partially into the recess defined
by the receptacle 46.4, such that horizontal movement of the trolley 46.2 with its
pot 45 and displacement means 46.1 is prevented when the key 43 is engaged with the
lid 42, the trolley 46.2 thus effectively being locked in position. Thus, the trolley
46.2 can only move the pot 45 into position in axial alignment with the port 40 when
the key 43 has been unlocked by removing it, i.e. unscrewing it, from the lid 42 and
stowing it in the receptacle 46.4 on the trolley 46.2 as shown in Figure 7. After
the key 43 has been so stored, the trolley 46.2 is slid laterally, thereby to bring
the pot 45 into axial alignment with the port 40.
[0076] The loading assembly 46 is further provided with a laterally, or horizontally, sliding
plate 46.5, which is operable to remove a lid 45.1 of the pot 45. In use, the hoist
mechanism 44 is hoists the pot 45 with its lid 45.1 of similar radiation opaque or
shielding material still in a closed condition, towards the port 40. When the lid
45.1 is positioned at the height of the horizontal sliding plate 46.5, which is mounted
transversely on the trolley, the lid 45.1 is clamped by a clamping mechanism (not
shown) of the sliding plate 46.5 and removed from the pot 45 so that the pot 45 is
opened. The open pot 45 is then further raised to its docking position against the
port 40. A docking position of the pot 45 is typically at a height where an upper
surface of the pot 45 is substantially flush or slightly raised above a rim of the
bottom loading port 40 on an inside of the chamber 16. Preferably, the lid 42 is only
opened from the inside of the cell 14 when the pot 45 is in this position, thereby
to provide access to a radiation source or sample material inside the pot 45. In this
configuration radiation leakage from any source or other radioactive material inside
the pot 45 is avoided as well as any accidental spillage of materials or dropping
of contaminated equipment from inside the handling chamber 16 through the port 40.
[0077] The loading assembly 46 is further configured to dock pots of different diameter
to the port 40. For each pot 45 of a diameter smaller than the maximum allowable diameter
a matching outer spacer ring or sleeve 45.2 is provided, preferably made of similar
radiation opaque material and with an outer diameter and shape to match that of the
carriage 44.4 as well as that of the port opening 40. Thus, the spacer 45.2 fits snugly
around the pot 45 such that, when the lid 45.1 has been removed, the pot 45 and spacer
45.2 invariably docks radiation leak free to the port 40 of the inner cell 14.
[0078] It will be appreciated that in use, after the radioactive source or sample has been
transported out of or back into the pot 45, the port 40 will be closed with the lid
42 from inside the cell 14, the pot 45 will be lowered, closed with its own lid 45.1
and removed from the loading port 40 and access means 41 in the reverse order of steps
indicated hereinbefore for the loading operation. The key 43 will then be replaced
and re-engaged with the lid 42 to restore the normal state of integrity as soon as
possible.
[0079] The outer housing 12 is further provided with access means to the 105-DPTE port 34.2
in the form of lead roller door 48 which closes an access opening 50 in the sidewall
20a of the outer housing 12 in a location corresponding to the location of the 105-DPTE
port 34.2 in the sidewall 18a of the inner cell.
[0080] A chamber 52 is provided as part of the outer housing 12, the chamber 52 being provided
with radiation monitoring and detection equipment (not visible) for monitoring radiation
emission from the assembly 10. In a preferred embodiment the radiation detection equipment
may be a so called ionization chamber, which detects any ionizing radiation. It will
be appreciated that, in such an embodiment, the chamber 52 may be the ionization chamber
itself. The assembly is also provided with warning means in the form of an alarm (not
illustrated) which is associated with the radiation monitoring and detection means
in the chamber 52 and is configured to indicate unacceptable radiation emission levels
from the assembly 10.
[0081] The inner cell 14 is provided with service connection means 54 on the endwall 18d
thereof, to which service connection means and external service conveying means for
conveying services such as electricity, gas, vacuum, water and compressed air to the
inner cells are connectable. The connection means 54 preferably includes a connection
port for a conveying means for each of these services.
[0082] The inner cell 14 is provided with a ventilation inlet 56 to the chamber 16 and an
exhaust outlet 58 from the chamber. For each of the inlet 56 and outlet 58 a filter
arrangement is provided (not shown) comprising two filter elements each, one inside
the cell 14 and the other outside the cell 14, but still within the outer housing
20 and in flow communication with the inner filter element. Service and replacement
of the inner filter element in each filter arrangement can be effected from inside
the chamber 16 by means of the handling means 28, i.e. without compromising chamber
integrity.
[0083] The filter arrangement on the ventilation inlet 56 of the inner cell 14 has a corresponding
service access means in the form of an opening in the outer housing 20, the opening
being shielded by a lead plug or stopper 56.1. The stopper 56.1 is removable to allow
replacement of the outer inlet filter element through the service access means.
[0084] The filter arrangement on the exhaust outlet 58 has a similar service access means
in the outer housing 20, for replacing an outer exhaust filter element, shielded by
a lead plug or stopper 58.1. The outer exhaust filter element of the exhaust outlet
58 is connected by means of an exhaust line to a ventilation system of a laboratory
or similar site where the handling assembly 10 is accommodated. The exhaust line is
guided radiation leak free through the plug 58.1 through a labyrinth channel in the
plug 58.1.
[0085] In use, with a view to handling radioactive material of a specific type and for a
specific purpose, the inner cell 14 is inserted into the outer housing 12 through
the sliding door arrangement 36 in a loaded condition, i.e. either pre-loaded with
the particular radioactive material or with the remains of a previous operation with
the same radioactive material. Alternatively, the inner cell 14 is inserted into the
outer housing 12 in an empty condition and the radioactive material is loaded into
the handling chamber 16 thereafter through the bottom loader port 40. Other nonradioactive
sample materials and equipment are typically loaded through the DPTE ports 34.1, 34.2.
When the inner cell 14 has been inserted into the outer housing 12, the control means
28 are connected to their associated handling means 26 and handling of the radioactive
material is carried out by operation of the handling means 26 as controlled by the
control means 28.
[0086] After completion, radioactive materials as well as other waste materials are unloaded
from the handling chamber 16 through the bottom loader port 40 and/or the DPTE ports
34.1, 34.2. The inner cell 14 is subsequently sealed and removed from the outer housing
12.
[0087] The present invention seeks to provide a multipurpose radioactive material handling
or containment assembly (or hot cell) having an increased versatility of use as compared
to conventional containment installations, particularly in terms of shortened decontamination
times and time required for conducting operations on different radioactive materials
therein, including the down time between successive operations. It is thus regarded
as an advantage of the invention as described that the use of separate inner cells
for each radioactive material which is handled in the assembly obviates, or significantly
reduces, the requirement of decontamination of the assembly before a different radioactive
material is handled therein, thus enabling a range of operations to be conducted without
extended decontamination operations delaying the sequential conducting of such operations
and without fear of cross-contamination between successive operations.
[0088] The angularly spaced positioning of handling means 26 and associated control means
28 in contrast to a co-planar arrangement, as is typically used in the art of the
invention, as well as the provision of the window 24 in the obliquely oriented wall
20e in the outer housing, as hereinbefore described, facilitates carrying out operations
inside the handling chamber 16 with increased versatility. More particularly, the
angular positioning of the handling means and associated control means, and their
location at different levels, has the effect that operating ranges of the handling
means inside the handling chamber overlap and that no so-called "dead space" below
or above the complementary handling and associated control means or in corners of
the cell exists as is commonly experienced in conventional handling facilities of
which the Applicant is aware. Further, the oblique positioning of the outer housing
window in combination with the inner cell window provides greater visibility into
all the areas of the inner cell affording a compact handling assembly with optimal
space utilisation of the inner cell.
[0089] Apart from the bottom loading port, access to and from the outer housing, even when
the inner cell is mounted therein, is conveniently facilitated by the sliding doors
36a, 36b comprising the endwall 20b of the outer assembly, as well as by the roller
door 48 which provides access to the 105-DPTE door 34.2 of the inner cell when it
is mounted inside the outer housing.
[0090] Furthermore, a significant advantage of the sliding doors 36a, 36b is afforded in
terms of ease of interchanging inner cells through this door assembly. Such interchange
of inner cells can be performed by merely removing the control means 28 and the outer
filter elements on top of the inner cell 14 as described hereinbefore, followed by
loosening the mountings on the assembly frame. In contrast, in conventional installations
known to the Applicant, removal of an inner compartment or chamber, if any, requires
at least the partial disassembly of the shielding walls and roof even in the so-called
modular arrangements found in the prior art.
[0091] It is regarded as an advantage of the invention that, when a range of operations
or routine tests on different radioactive materials are being conducted, the use of
only one assembly is required due to the interchangeability of the inner cells of
the assembly. Conventionally, in order to conduct operations on different radioactive
materials, a plurality of conventional containment installations is required: one
for each radioactive material or group of compatible materials and with the inevitable
duplication of at least most of the handling equipment. The assembly of the present
invention is thus compact in the sense that space is saved in a laboratory, or any
other location in which it is provided, by the use of only one assembly and a single
compact storage space for the different inner cells, which typically only requires
shielding of the equivalent of not more than 10mm lead and no ventilation during storage.
[0092] A further advantage of the invention as described is that high containment integrity
is maintained by the assembly, despite the continuous interchange of inner cells.
This is possible due to the configuration of the bottom loading port of the inner
cell and the associated container displacement means of the outer housing, which enables
safe and contained loading of radioactive materials into and out of the inner cell
when mounted in the outer housing. The configuration of the ventilation inlets and
exhausts, as described, also contributes to maintaining high containment integrity.
A significant consequential advantage of this high containment integrity combined
with the interchangeability of the inner cells is that cross-contamination is avoided
between successive operations with different radioactive materials.
[0093] It is yet a further advantage of the invention as described that inner cells can
be reused for handling the same radioactive material and do not need to be discarded.
This also reduces the production of radioactive waste resulting from decontamination.
[0094] Yet a further advantage of the invention is that each inner cell is provided with
its own handling means therein. This enables selective handling and other services
to be provided in each cell according to requirements of service to be carried out
in that cell. This use of separate handling means and other service means in each
inner cell further reduces the decontamination requirement of the assembly.
[0095] Another advantage of the invention is that, should decontamination of an inner cell
be required, such decontamination can be carried out by substituting the flexible
attachment means (or boots) for gloves and also installing gloves in the DPTE ports,
thereby enabling manual decontamination to be carried out.
[0096] Yet another advantage of the invention is that the radioactive material container
displacement means of the loading assembly is configured to handle containers or pots
always in an upright condition, thereby further reducing the risk of radiation exposure.
[0097] The assembly is further adaptable in the sense that further shielding means, such
as Perspex™ or polycarbonate screens, may be provided at sections with minimal shielding,
thereby to provide further protection against radiation exposure.
[0098] To demonstrate some of these advantages, the Applicant established, on a prototype
handling assembly or facility according to the invention, that the inner cells can
typically be interchanged by one or two persons in less than four hours. This includes
detaching all the handling means and other external devices and service connections
from the removed inner cell and reattaching the same after the replacement inner cell
has been inserted and fitted, but excludes the required containment checks such as
measuring radiation levels around the inner cell and taking sample smears for possible
contamination on the outside of the inner cell as it is being removed from the outer
housing. It also includes the removal of certain sections of lead shielding from the
outer housing such as the ventilation port stoppers 56.1 and 58.1 to disconnect and
remove the outer filter elements from the inlet and outlet ventilation lines respectively.
This amounts to less than about 3% of the total mass of lead used in the outer housing
shielding of the prototype handling facility.
[0099] In contrast, in order to prepare a conventional handling facility, which does not
feature the interchangeable inner cells of the present invention, to handle a different
radioactive species, including the actions required to decontaminate and prepare the
facility for the next species in accordance with the standards commonly known in the
art, will typically take at least one week, and in some cases up to several months,
depending on the extent to which the contaminating species have penetrated and/or
are attached to the inner walls of the facility.
[0100] The applicant has also found that a typical inner cell storage space with a capacity
of at least six inner cells and provided with the said shielding of not more than
10 mm lead will take up a floor space about equal to that of the handlingassembly
itself.
1. A radioactive material handling assembly (10), which includes
an outer housing (12);
an inner cell (14) which defines a radioactive material containment / handling chamber
(16) and which is individually removably mountable inside the outer housing, the inner
cell being complementary in shape to the outer housing when both are seen in horizontal
section such that, when the inner cell is mounted inside the outer housing, each wall
(18a, 18b, 18c, 18d, 18e) of the inner cell is adjacent a corresponding wall (20a,
20b, 20c, 20d, 20e) of the outer housing, the inner cell being interchangeable with
a plurality of other inner cells which are individually removably mountable inside
the outer housing; and
handling means (26) operable from outside the inner cell to handle radioactive materials
located in the containment / handling chamber, with at least one of the outer housing
and the inner cell being predominantly of a shielding material which is opaque to
radioactivity, wherein
two of the handling means (26) are provided, the handling means being mounted to respective
walls (18b, 18c) of the inner cell, which walls are angularly spaced relative to each
other about a vertical line of intersection between the walls or projections thereof
such that the handling means are thus also angularly spaced from each other, when
the cell (14) is seen in plan view,
2. An assembly (10) according to Claim 1, characterized in that the handling means (26) comprise manipulating means (26) inside the containment /
handling chamber, and attachment means (30) connecting the manipulating means to a
wall (18b, 18c) of the inner cell (14), the attachment means configured to enable
movement of the manipulating means.
3. An assembly (10) according to Claim 2, characterized in that it includes control means (28) for the handling means, the control means, in use,
being operable to control operation of the handling means from a position remote from
the containment / handling chamber (16).
4. An assembly (10) according to Claim 3, characterized in that the control means (28)comprises a control rod (28.1), one end portion of the control
rod being connected to the handling means and the other end portion of the control
rod extending beyond the confines of the outer housing (12) and being provided with
a user control interface (28.2).
5. An assembly (10) according to Claim 4, characterized in that the control rod (28.1) is pivotally mounted in a wall (20b, 20c) of the outer housing
(12) by means of a pivotal mounting (32), thereby to direct pivotal movement of the
handling means (26).
6. An assembly (10) according to any one of Claims 1 to 5, characterized in that the angularly spaced walls (18b, 18c), and thus the two handling means (26), are
at an angular spacing of 90° to each other.
7. An assembly (10) according to any one of Claims 1 to 6, characterized in that it includes viewing means in the outer housing (12) and the inner cell (14), for
visual inspection of radioactive materials contained in and being handled inside the
containment / handling chamber (16) when the inner cell is mounted inside the outer
housing.
8. An assembly (10) according to Claim 7, characterized in that the viewing means is in the form of a window (22) in a wall of the inner cell (14)
and a window (24) in the wall (20e) of the outer housing (12), the windows (22, 24)
providing a line of sight from a position external to the assembly, to the containment
/ handling chamber (16) when the inner cell is mounted inside the outer housing.
9. An assembly (10) according to Claim 8, characterized in that at least one of the windows (22, 24) is of radiation opaque material having a radiation
shielding power equivalent to at least 75mm lead.
10. An assembly (10) according to Claim 8 or Claim 9, characterized in that at least one of the windows (24) is provided in a connecting wall (20e) which connects
the angularly spaced walls (20b, 20c) in which the two handling means (26) are, respectively,
provided.
11. An assembly (10) according to Claim 10, characterized in that the connecting wall (20e) is obliquely oriented relative to the angularly spaced
walls (20b, 20c).
12. An assembly (10) according to any one of Claims 1 to 11, characterized in that the handling means (26) are positioned at different levels in the inner cell (14)
and outer housing (12), the handling means thus being vertically spaced from each
other.
13. An assembly (10) according to any one of Claims 1 to 12, characterized in that the inner cell (14) is provided with containment / handling chamber access means
(34.1, 34.2) for introducing materials into, and withdrawing materials out of, the
containment / handling chamber (16).
14. An assembly (10) according to Claim 14, characterized in that the containment / handling chamber access means (34.1, 34.2) comprises an inner and
an outer door assembly such that the integrity of the containment / handling chamber
is not compromised during the introduction of materials into, or withdrawal of materials
out of, the containment / handling chamber.
15. An assembly (10) according to any one of Claims 1 to 14, characterized in that the inner cell (14) is provided with a bottom loading port (40) for loading materials
into and out of the containment / handling chamber (16) through the bottom of the
cell, and closing means (42) which closes and seals the bottom loading port from the
inside of the containment / handling chamber.
16. An assembly (10) according to Claim 15, characterized in that the outer housing (12) is provided with bottom loading port access means (41) associated
with and providing access to the bottom loading port (40) of the inner cell (14) from
outside the assembly, when the inner cell is mounted in the outer housing.
17. An assembly (10) according to Claim 16 characterized in that it includes, on the outer housing (12), a container loading assembly (46) comprising
container displacement means (46.1) for docking containers (45) against the bottom
loading port (40) through the bottom loading port access means (41).
18. An assembly (10) according to Claim 17, characterized in that the container displacement means (46.1) includes hoisting means (44) for hoisting
a container towards the bottom loading port (40).
19. An assembly (10) according to Claim 18, characterized in that the loading assembly (46) is configured to dock containers (45) of different diameter
to the bottom loading port by having mounted to the hoisting means (44), for each
container of a particular diameter, a matching outer spacer ring or sleeve (45.2)
for receiving the container, with the outer spacer, ring or sleeve having a fixed
outer diameter and shaped to match a carriage (44.4) of the hoisting means as well
as the bottom loading port opening.
20. An assembly (10) according to any one of Claims 1 to 19, characterized in that the inner cell (14) is provided with at least one ventilation inlet (56) to the containment
/ handling chamber (16) and at least one exhaust outlet (58) from the containment
/ handling chamber, with the ventilation inlet and outlet exhaust being provided,
respectively, with inlet and outlet filters.
21. A method of operating a radioactive material handling assembly (10) according to any
one of Claims 1 to 20, to handle radioactive materials therein, the method including
inserting, individually, an initial or first inner cell (14) into the outer housing
(12) of the assembly such that the initial or first inner cell is individually mounted
inside the outer housing with each wall (18a, 18b, 18c, 18d, 18e) thereof being adjacent
a corresponding wall (20a, 20b, 20c, 20d, 20e) of the outer housing;
handling an initial or first radioactive material inside the containment / handling
chamber (16) of the initial or first inner cell from a position outside the outer
housing;
removing the initial or first inner cell from the outer housing; and
inserting a second inner cell (14) into the outer housing after removal of the initial
or first inner cell from the outer housing and handling a second radioactive material
inside the containment / handling chamber (16) of the second inner cell, the second
radioactive material being different to the initial or first radioactive material,
characterized in that
the handling of the radioactive materials inside the containment / handling chambers
(16) of the inner cells (14) is effected by means of two handling means (26) mounted
to respective walls (18b, 18c) of the inner cells, which walls are angularly spaced
relative to each other about a vertical line of intersection between the walls or
projections thereof such that the handling means are thus also angularly spaced from
each other, when the cells are seen in plan view.
1. Handhabungsanordnung von radioaktivem Material (10), Folgendes umfassend:
ein Außengehäuse (12);
eine Innenzelle (14), die eine Sicherheits-/ Handhabungskammer (16) für radioaktives
Material definiert und im Inneren des Außengehäuses individuell lösbar montierbar
ist,
wobei im Horizontalschnitt betrachtet die Innenzelle formkomplementär zu dem Außengehäuse
ausgebildet ist, so dass jede Wand (18a, 18b, 18c, 18d, 18e) der Innenzelle an eine
korrespondierende Wand (20a, 20b, 20c, 20d, 20e) des Außengehäuses angrenzt, wenn
die Innenzelle im Inneren des Außengehäuses montiert ist, wobei die Innenzelle mit
einer Vielzahl weiterer Innenzellen, die im Inneren des Außengehäuses individuell
lösbar montiert werden können, auswechselbar ist, sowie Handhabungsmittel (26), die
von außerhalb der Innenzelle zum Handhaben radioaktiver Materialien, die sich in der
Sicherheits-/ Handhabungskammer befinden,
betätigbar sind, wobei das Außengehäuse oder die Innenzelle oder beide überwiegend
aus einem für Radioaktivität undurchlässigen Abschirmmaterial bestehen,
wobei
die Handhabungsmittel (26) zweifach bereitgestellt sind, die Handhabungsmittel an
entsprechenden Wänden (18b, 18c) der Innenzelle befestigt sind und diese Wände unter
Bildung eines Winkels um eine vertikale Schnittlinie zwischen den Wänden oder
Projektionen derselben voneinander beabstandet sind, so dass, wenn man die Zelle (14)
in der Draufsicht betrachtet, die Handhabungsmittel dementsprechend ebenfalls unter
Bildung eines Winkels voneinander beabstandet sind.
2. Anordnung (10) nach Anspruch 1, dadurch gekennzeichnet, dass die Handhabungsmittel (26) im Inneren der Sicherheits-/ Handhabungskammer Handhaben
(26), sowie Befestigungsmittel (30) umfassen, welche die Handhaben mit einer Wand
(18b, 18c) der Innenzelle (14) verbinden, wobei die Befestigungsmittel so eingerichtet
sind, dass sie die Bewegung der Handhaben ermöglichen.
3. Anordnung (10) nach Anspruch 2, dadurch gekennzeichnet, dass sie Steuermittel (28) für die Handhabungsmittel umfasst, wobei die Steuermittel betätigbar
sind, beim Gebrauch den Betrieb der Handhabungsmittel von einer von der Sicherheits-/
Handhabungskammer (16) entfernten Position zu steuern.
4. Anordnung (10) nach Anspruch 3, dadurch gekennzeichnet, dass das Steuermittel (28) eine Steuerstange (28.1) umfasst, wobei ein Endabschnitt der
Steuerstange mit dem Handhabungsmittel verbunden ist und der andere Endabschnitt der
Steuerstange sich über die Begrenzung des Außengehäuses (12) hinaus erstreckt und
mit einer Benutzersteuerschnittstelle (28.2) ausgestattet ist.
5. Anordnung (10) nach Anspruch 4, dadurch gekennzeichnet, dass die Steuerstange (28.1) durch ein Schwenklager (32) drehgelenkig in einer Wand (20b,
20c) des Außengehäuses (12) gelagert ist, um die Schwenkbewegung des Handhabungsmittels
(26) zu lenken.
6. Anordnung (10) nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, dass die unter einem Winkel beabstandeten Wände (18b, 18c) und auf diese Weise die beiden
Handhabungsmittel (26) in einem Winkel von 90° zueinander angeordnet sind.
7. Anordnung (10) nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, dass sie in dem Außengehäuse (12) und der Innenzelle (14) Sichtmittel für die Sichtprüfung
radioaktiver Materialien umfasst, die im Inneren der Sicherheits-/ Handhabungskammer
(16) aufgenommen sind und gehandhabt werden, wenn die Innenzelle im Inneren des Außengehäuses
montiert ist.
8. Anordnung (10) nach Anspruch 7, dadurch gekennzeichnet, dass das Sichtmittel die Form eines Fensters (22) in einer Wand der Innenzelle (14) und
eines Fensters (24) in der Wand (20e) des Außengehäuses (12) besitzt, wobei die Fenster
(22, 24) eine Sichtverbindung von einer Position außerhalb der Anordnung bis zu der
Sicherheits-/ Handhabungskammer (16) bereitstellen, wenn die Innenzelle im Inneren
des Außengehäuses montiert ist.
9. Anordnung (10) nach Anspruch 8, dadurch gekennzeichnet, dass mindestens eines der Fenster (22, 24) aus strahlungsundurchlässigem Material besteht,
dessen Strahlungs-Abschirmvermögen mindestens dem von 75 mm Blei entspricht.
10. Anordnung (10) nach Anspruch 8 oder Anspruch 9, dadurch gekennzeichnet, dass mindestens eines der Fenster (24) in einer Verbindungswand (20e) bereitgestellt ist,
welche die unter Bildung eines Winkels beabstandeten Wände (20b, 20c) verbindet, in
denen jeweils eines der Handhabungsmittel (26) bereitgestellt ist.
11. Anordnung (10) nach Anspruch 10, dadurch gekennzeichnet, dass die Verbindungswand (20e) schräg zu den unter Bildung eines Winkels beabstandeten
Wänden (20b, 20c) ausgerichtet ist.
12. Anordnung (10) nach einem der Ansprüche 1 bis 11, dadurch gekennzeichnet, dass die Handhabungsmittel (26) in der Innenzelle (14) und dem Außengehäuse (12) in unterschiedlicher
Höhe angeordnet sind, wodurch die Handhabungsmittel vertikal voneinander beabstandet
sind.
13. Anordnung (10) nach einem der Ansprüche 1 bis 12, dadurch gekennzeichnet, dass die Innenzelle (14) mit Zugangsmitteln (34.1, 34.2) zu der Sicherheits-/ Handhabungskammer
zur Eingabe und Entnahme von Materialien in die bzw. aus der Sicherheits-/ Handhabungskammer
(16) ausgestattet ist.
14. Anordnung (10) nach Anspruch 13, dadurch gekennzeichnet, dass das Zugangsmittel (34.1, 34.2) zu der Sicherheits-/ Handhabungskammer eine innere
und eine äußere Türanordnung umfasst, so dass die Integrität der Sicherheits-/ Handhabungskammer
während der Eingabe oder Entnahme von Materialien in die bzw. aus der Sicherheits-/
Handhabungskammer (16) nicht beeinträchtigt wird.
15. Anordnung (10) nach einem der Ansprüche 1 bis 14, dadurch gekennzeichnet, dass die Innenzelle (14) mit einer unteren Ladeöffnung (40) zum Einbringen und Entfernen
von Materialien in die bzw. aus der Sicherheits-/ Handhabungskammer (16) durch die
Zellenunterseite ausgestattet ist, sowie mit einem Verschlussmittel (42), das die
untere Ladeöffnung von der Innenseite der Sicherheits-/ Handhabungskammer her schließt
und abdichtet.
16. Anordnung (10) nach Anspruch 15, dadurch gekennzeichnet, dass das Außengehäuse (12) mit Zugangsmitteln (41) zu der unteren Ladeöffnung ausgestattet
ist, die, wenn die Innenzelle im Inneren des Außengehäuses montiert ist, einen Zugang
von außerhalb der Anordnung zu der unteren Ladeöffnung (40) der Innenzelle (14) bereitstellen
und mit dieser verbunden sind.
17. Anordnung (10) nach Anspruch 16, dadurch gekennzeichnet, dass sie an dem Außengehäuse (12) eine Behälter-Ladeanordnung (46) mit Behälter-Verschiebemitteln
(46.1) umfasst, um Behälter (45) durch die Zugangsmittel (41) zu der unteren Ladeöffnung
hindurch an der unteren Ladeöffnung (40) anzudocken.
18. Anordnung (10) nach Anspruch 17, dadurch gekennzeichnet, dass die Behälter-Verschiebemittel (46.1) Hebemittel (44) zum Anheben eines Behälters
zu der unteren Ladeöffnung (40) umfassen.
19. Anordnung (10) nach Anspruch 18, dadurch gekennzeichnet, dass die Ladeanordnung (46) dazu ausgelegt ist, Behälter (45) unterschiedlichen Durchmessers
an der unteren Ladeöffnung anzudocken, indem an den Hebemitteln (44) für jeden Behälter
mit einem bestimmten Durchmesser ein passender äußerer Distanzring oder eine passende
äußere Distanzhülse (45.2) zur Aufnahme des Behälters angebracht ist, wobei der äußere
Abstandhalter, der Ring oder die Hülse einen festgelegten Außendurchmesser hat und
an einen Schlitten (44.4) des Hebemittels sowie an die Öffnung der unteren Ladeöffnung
formangepasst ist.
20. Anordnung (10) nach einem der Ansprüche 1 bis 19, dadurch gekennzeichnet, dass die Innenzelle (14) mit mindestens einem Belüftungseinlass (56) zu der Sicherheits-/
Handhabungskammer (16) und mindestens einem Entlüftungsauslass (58) aus der Sicherheits-/
Handhabungskammer ausgestattet ist, wobei der Belüftungseinlass mit Einlass- und der
Entlüftungsauslass mit Auslassfiltern versehen ist.
21. Betriebsverfahren einer Handhabungsanordnung von radioaktivem Material (10) nach einem
der Ansprüche 1 bis 20, zur Handhabung radioaktiver Materialien im Inneren der Anordnung,
wobei das Verfahren Folgendes umfasst:
Individuelles Einsetzen einer ursprünglichen oder ersten Innenzelle (14) in das Außengehäuse
(12) der Anordnung, so dass die ursprüngliche oder erste Innenzelle individuell innerhalb
des Außengehäuses montiert ist, wobei jede ihrer Wände (18a, 18b, 18c, 18d, 18e) an
eine korrespondierende Wand (20a, 20b, 20c, 20d, 20e) des Außengehäuses angrenzt;
Handhabung eines ursprünglichen oder ersten radioaktiven Materials im Inneren der
Sicherheits-/ Handhabungskammer (16) der ursprünglichen oder ersten Innenzelle von
einer Position außerhalb der Anordnung aus;
Entfernen der ursprünglichen oder ersten Innenzelle aus dem Außengehäuse und Einsetzen
einer zweiten Innenzelle (14) in das Außengehäuse nach dem Entfernen der ursprünglichen
oder ersten Innenzelle aus dem Außengehäuse, sowie Handhabung eines zweiten radioaktiven
Materials im Inneren der Sicherheits-/ Handhabungskammer (16) der zweiten Innenzelle,
wobei das zweite radioaktive Material von dem ursprünglichen oder ersten radioaktiven
Material verschieden ist,
dadurch gekennzeichnet, dass
die Handhabung der radioaktiven Materialien innerhalb der
Sicherheits-/ Handhabungskammern (16) der Innenzellen (14) mit Hilfe zweier Handhabungsmittel
(26) vorgenommen wird, die an entsprechenden Wänden (18b, 18c) der Innenzellen befestigt
sind, wobei diese Wände unter Bildung eines Winkels um eine vertikale Schnittlinie
zwischen den Wänden oder Projektionen derselben voneinander beabstandet sind, so dass,
wenn man die Zellen in der Draufsicht betrachtet, die Handhabungsmittel dementsprechend
ebenfalls unter Bildung eines Winkels voneinander beabstandet sind.
1. Ensemble de manutention de matières radioactives (10), qui comporte
un boîtier externe (12) ;
une cellule interne (14) qui définit une chambre de confinement/manutention (16) de
matières radioactives et qui peut être individuellement montée de manière amovible
à l'intérieur du boîtier externe, la cellule interne étant de forme complémentaire
au boîtier externe lorsque les deux sont regardés en coupe horizontale de sorte que,
lorsque la cellule interne est montée à l'intérieur du boîtier externe, chaque paroi
(18a, 18b, 18c, 18d, 18e) de la cellule interne soit adjacente à une paroi correspondante
(20a, 20b, 20c, 20d, 20e) du boîtier externe, la cellule interne étant interchangeable
avec une pluralité d'autres cellules internes qui peuvent être individuellement montées
de manière amovible à l'intérieur du boîtier externe ; et
des moyens de manutention (26) pouvant fonctionner depuis l'extérieur de la cellule
interne pour manier des matières radioactives placées dans la chambre de confinement/manutention,
avec au moins l'un(e) du boîtier externe et de la cellule interne est essentiellement
constitué(e) d'un matériau de blindage qui est opaque à la radioactivité, où
deux moyens parmi les moyens de manutention (26) sont prévus, les moyens de manutention
étant montés sur des parois respectives (18b, 18c) de la cellule interne, lesquelles
parois sont espacées de manière angulaire l'une par rapport à l'autre autour d'une
ligne verticale d'intersection entre les parois ou leurs projections de sorte que
les moyens de manutention soient donc également espacés de manière angulaire l'un
par rapport à l'autre, lorsque la cellule (14) est regardée dans une vue en plan.
2. Ensemble (10) selon la revendication 1, caractérisé en ce que les moyens de manutention (26) comprennent un moyen de manipulation (26) à l'intérieur
de la chambre de confinement/manutention, et des moyens de fixation (30) reliant le
moyen de manipulation à une paroi (18b, 18c) de la cellule interne (14), les moyens
de fixation étant configurés pour permettre le mouvement du moyen de manipulation.
3. Ensemble (10) selon la revendication 2, caractérisé en ce qu'il comporte un moyen de commande (28) pour les moyens de manutention, le moyen de
commande, en cours d'utilisation, pouvant fonctionner pour commander le fonctionnement
des moyens de manutention à partir d'une position éloignée de la chambre de confinement/manutention
(16).
4. Ensemble (10) selon la revendication 3, caractérisé en ce que le moyen de commande (28) comprend une tige de commande (28.1), une partie d'extrémité
de la tige de commande étant reliée aux moyens de manutention, et l'autre partie d'extrémité
de la tige de commande s'étendant au-delà des limites du boîtier externe (12) et étant
dotée d'une interface de commande utilisateur (28.2).
5. Ensemble (10) selon la revendication 4, caractérisé en ce que la tige de commande (28.1) est montée de manière pivotante dans une paroi (20b, 20c)
du boîtier externe (12) au moyen d'un montage pivotant (32), de manière à diriger
le mouvement de pivotement des moyens de manutention (26).
6. Ensemble (10) selon l'une quelconque des revendications 1 à 5, caractérisé en ce que les parois espacées de manière angulaire (18b, 18c), et ainsi les deux moyens de
manutention (26), se trouvent à un espacement angulaire de 90° l'un par rapport à
l'autre.
7. Ensemble (10) selon l'une quelconque des revendications 1 à 6, caractérisé en ce qu'il comporte un moyen de visualisation dans le boîtier externe (12) et la cellule interne
(14), destiné à l'inspection visuelle des matières radioactives contenues dans la
chambre de confinement/manutention (16) et étant maniées à l'intérieur de celle-ci
lorsque la cellule interne est montée à l'intérieur du boîtier externe.
8. Ensemble (10) selon la revendication 7, caractérisé en ce que le moyen de visualisation se présente sous la forme d'une fenêtre (22) dans une paroi
de la cellule interne (14) et d'une fenêtre (24) dans la paroi (20e) du boîtier externe
(12), les fenêtres (22, 24) fournissant une ligne de visée à partir d'une position
extérieure à l'ensemble, vers la chambre de confinement/manutention (16) lorsque la
cellule interne est montée à l'intérieur du boîtier externe.
9. Ensemble (10) selon la revendication 8, caractérisé en ce qu'au moins l'une des fenêtres (22, 24) est réalisée en matériau opaque aux rayonnements
ayant une puissance de blindage contre les rayonnements équivalente à au moins 75
mm de plomb.
10. Ensemble (10) selon la revendication 8 ou 9, caractérisé en ce qu'au moins l'une des fenêtres (24) est prévue dans une paroi de liaison (20e) qui relie
les parois espacées de manière angulaire (20b, 20c) où les deux moyens de manutention
(26) sont, respectivement, prévus.
11. Ensemble (10) selon la revendication 10, caractérisé en ce que la paroi de liaison (20e) est obliquement orientée par rapport aux parois espacées
de manière angulaire (20b, 20c).
12. Ensemble (10) selon l'une quelconque des revendications 1 à 11, caractérisé en ce que les moyens de manutention (26) sont positionnés à des niveaux différents dans la
cellule interne (14) et le boîtier externe (12), les moyens de manutention étant ainsi
verticalement espacés l'un de l'autre.
13. Ensemble (10) selon l'une quelconque des revendications 1 à 12, caractérisé en ce que la cellule interne (14) est dotée d'un moyen d'accès (34.1, 34.2) à la chambre de
confinement/manutention pour introduire des matières dans la chambre de confinement/manutention
(16) et pour en retirer des matières.
14. Ensemble (10) selon la revendication 14, caractérisé en ce que le moyen d'accès à la chambre de confinement/manutention (34.1, 34.2) comprend un
ensemble de porte interne et un ensemble de porte externe de sorte que l'intégrité
de la chambre de confinement/manutention ne soit pas compromise durant l'introduction
de matières dans la chambre de confinement/manutention, ou durant le retrait de matières
de la chambre de confinement/manutention.
15. Ensemble (10) selon l'une quelconque des revendications 1 à 14, caractérisé en ce que la cellule interne (14) est dotée d'un orifice de chargement inférieur (40) servant
à charger des matières dans la chambre de confinement/manutention (16) et à extraire
des matières de celle-ci à travers le fond de la cellule, et d'un moyen de fermeture
(42) qui est destiné à fermer et à rendre étanche l'orifice de chargement inférieur
à partir de l'intérieur de la chambre de confinement/manutention.
16. Ensemble (10) selon la revendication 15, caractérisé en ce que le boîtier externe (12) est doté d'un moyen d'accès à l'orifice de chargement inférieur
(41) associé à l'orifice de chargement inférieur (40) de la cellule interne (14) à
partir de l'extérieur de l'ensemble et fournissant l'accès à celui-ci, lorsque la
cellule interne est montée dans le boîtier externe.
17. Ensemble (10) selon la revendication 16, caractérisé en ce qu'il comporte, sur le boîtier externe (12), un ensemble de chargement de récipient (46)
comprenant un moyen de déplacement de récipient (46.1) permettant d'amarrer des récipients
(45) contre l'orifice de chargement inférieur (40) à travers le moyen d'accès à l'orifice
de chargement inférieur (41).
18. Ensemble (10) selon la revendication 17, caractérisé en ce que le moyen de déplacement de récipient (46.1) comporte un moyen de levage (44) destiné
à soulever un récipient vers l'orifice de chargement inférieur (40).
19. Ensemble (10) selon la revendication 18, caractérisé en ce que l'ensemble de chargement (46) est configuré pour amarrer les récipients (45) de différents
diamètres à l'orifice de chargement inférieur en ayant monté sur le moyen de levage
(44), pour chaque récipient ayant un diamètre particulier, un anneau ou un manchon
d'espacement externe d'accouplement (45.2) destiné à recevoir le récipient, avec l'anneau
ou le manchon d'espacement externe ayant un diamètre externe fixe mis en forme de
manière à correspondre au chariot (44.4) du moyen de levage, ainsi qu'à l'ouverture
de l'orifice de chargement inférieur.
20. Ensemble (10) selon l'une quelconque des revendications 1 à 19, caractérisé en ce que la cellule interne (14) est dotée d'au moins une entrée de ventilation (56) à la
chambre de confinement/manutention (16) et d'au moins une sortie d'échappement (58)
de la chambre de confinement/manutention, avec l'entrée de ventilation et la sortie
d'échappement étant dotées, respectivement, de filtres d'entrée et de sortie.
21. Procédé de fonctionnement d'un ensemble de manutention de matières radioactives (10)
selon l'une quelconque des revendications 1 à 20, permettant de manier des matières
radioactives dedans, le procédé comportant le fait
d'insérer, de manière individuelle, une première cellule interne ou une cellule initiale
interne (14) dans le boîtier externe (12) de l'ensemble de sorte que la première cellule
interne ou la cellule initiale interne soit montée individuellement à l'intérieur
du boîtier externe avec chaque paroi (18a, 18b, 18c, 18d, 18e) de celle-ci est adjacente
à une paroi correspondante (20a, 20b, 20c, 20d, 20e) du boîtier externe ;
de manier une première matière radioactive ou une matière radioactive initiale à l'intérieur
de la chambre de confinement/manutention (16) de la première cellule interne ou la
cellule interne initiale à partir d'une position à l'extérieur du boîtier externe
;
de retirer la première cellule interne ou la cellule interne initiale du boîtier externe
; et
d'insérer une deuxième cellule interne (14) dans le boîtier externe après le retrait
de la première cellule interne ou la cellule interne initiale du boîtier externe et
de manier une deuxième matière radioactive à l'intérieur de la chambre de confinement/manutention
(16) de la deuxième cellule interne, la deuxième matière radioactive étant différente
de la première matière radioactive ou la matière radioactive initiale,
caractérisé en ce que
la manutention des matières radioactives à l'intérieur de la chambre de confinement/manutention
(16) des cellules internes (14) est effectuée au moyen de deux moyens de manutention
(26) montés sur des parois respectives (18b, 18c) des cellules internes, lesquelles
parois sont espacées de manière angulaire l'une par rapport à l'autre autour d'une
ligne verticale d'intersection entre les parois ou leurs projections de sorte que
les moyens de manutention soient, par conséquent, espacés de manière angulaire l'un
de l'autre, lorsque les cellules sont regardées dans une vue en plan.